DENVER—A coalition studying the potential for storing carbon under the Rocky Mountains says that based on preliminary data, it estimates northwest Colorado could possibly store up to 4.6 billion tons of carbon dioxide emissions underground.

The Rocky Mountain Carbon Capture and Sequestration Partnership said Thursday a final analysis won’t be ready until 2013.

The partnership is a coalition of government, academic and industry interests including the Colorado Geological Survey in states including Colorado, Arizona, New Mexico and Utah.

An $8.8 million federal grant is helping the group study possibilities for sequestering carbon emissions from power plants and industrial sources in deep-saline aquifers, which could reduce greenhouse gases. Researchers say deep-saline aquifers aren’t great resources for drinking water but show potential for being able to store carbon dioxide long-term.